Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities:
Net cash provided by operating activities	$ 261,940	$ 481,107
Proceeds from sales, maturities and redemptions of investments:
Fixed maturities, available-for-sale	2,130,539	3,132,414
Mortgage loans on real estate	223,785	209,888
Limited partnership interests and other investments	4,438	6,425
Purchases of investments:
Fixed maturities, available-for-sale	(2,108,487)	(2,840,513)
Mortgage loans on real estate	(536,765)	(565,217)
Limited partnership interests and other investments	(15,581)	(8,114)
Net change in short-term investments	81,207	(612,835)
Net change in policy loans	3,783	(9,037)
Purchases of furniture, equipment, and software	(26,247)	(21,710)
Net cash used in investing activities	(243,328)	(708,699)
Cash flows from financing activities:
Contract deposits	1,330,196	1,405,204
Contract withdrawals	(1,176,725)	(1,087,940)
Proceeds from surplus note issued to parent	346,218	0
Redemption of surplus note issued to parent	(333,400)	0
Dividends paid	(99,894)	(137,301)
Capital contribution	1,688	76,429
Payments for and interest paid on financing element derivatives, net	(1,673)	(3,461)
Net change in commercial paper borrowings	(505)	(27,796)
Net change in book overdrafts	(13,590)	1,623
Employee taxes paid for withheld shares	(32)	(648)
Net cash provided by financing activities	52,283	226,110
Net increase (decrease) in cash and cash equivalents	70,895	(1,482)
Cash and cash equivalents, beginning of year	17,211	18,321
Cash and cash equivalents, end of period	88,106	16,839
Net cash paid during the year for:
Income taxes	(9,323)	(10,449)
Interest	(16,194)	(12,931)
Non-cash investing and financing transactions during the years:
Share-based compensation expense	432	925
Fair value of assets acquired in settlement of fixed maturity investments	$ 28,315	$ 0